This invention is related generally to overhead industrial light fixtures.
A wide variety of overhead industrial light fixtures exist to serve needs such as factory and warehouse illumination and the like, and a number of advances have been made over the years. However, existing overhead industrial light fixtures have a number of problems and shortcomings, and it is to addressing such problems and shortcomings that this invention is directed.
Of particular concern is that many overhead industrial light fixtures of the prior art are unwieldy in size and shape, which makes them expensive to manufacture, expensive to ship and store, difficult to install and service, in some cases unattractive in appearance and even unacceptable or difficult to use in certain size-restricted applications.
Certain problems in the field of overhead industrial light fixtures are associated with the desirability of having standardized parts such as housings while still accommodating mounting of light fixtures having different weight distribution properties based on specified ballasts, capacitors, reflectors, etc. Certain components, including reflectors and ballasts vary in size, shape and weight. For example, glass reflectors tend to be substantially heavier than plastic or sheet metal reflectors. Ballasts, which are usually the heaviest components in overhead industrial light fixtures are of such weight that they are often mounted separate from the housing. Uneven weight distribution of a light fixture tends to cause problems in achieving a balanced mounting arrangement.
In the prior art there have been some efforts to provide mounting adjustments to accommodate varying weight distributions. For example, some devices of the prior art involve infinite adjustability of, for example, a sliding positioner which is operable within a specified range. Such infinite adjustability typically requires particular care, and sometimes trial and error mounting in order to achieve a satisfactory balance which will allow the light fixture to remain in the proper orientation when mounted. It is desirable to simplify the process of achieving proper balance in the mounting of overhead industrial light fixtures.
This invention addresses such problems and shortcomings.
It is an object of this invention to provide an improved overhead industrial light fixture overcoming some of the problems and shortcomings of the prior art.
Another object is to provide an improved overhead industrial light fixture that is easy and inexpensive to manufacture and easy to install and service.
Another object of this invention is to provide an improved overhead industrial light fixture facilitating balanced installation and eliminating the problems associated with infinitely adjustable mounting apparatus.
Another object of this invention is to provide an improved overhead industrial light fixture which provides a specific number of predetermined balance settings corresponding to specific weight distributions based on components used.
Another object of this invention is to provide an improved overhead industrial light fixtures which provides a number of convenient mounting options regardless of whether the light fixture is mounted to a junction box or to other overhead structure.
These and other objects of the invention will be apparent from the following descriptions and from the drawings.
This invention is an improvement in overhead light fixtures of the type including a housing with a top wall, power-related components (e.g., a ballast, a capacitor and an ignitor), a lamp-mounting socket, and usually a reflector.
In the improved overhead light fixture of this invention, the top wall, which has inner and outer surfaces (i.e., a surface facing the inside of the housing and a surface facing up), has a center region which defines a pair of adjacent hanger-member apertures through it. A particular form of hanger is placed in a chosen one of the hanger-member apertures, and is configured to engage the housing at one of such apertures in one of two selected orientations.
The hanger member is formed of a series of portions including (a) a base portion which is secured to the top-wall inner surface adjacent to a chosen one of the hanger-member apertures, (b) a through portion extending through the chosen aperture, (c) an offsetting portion extending from the through portion laterally along the top-wall outer surface, and (d) an offset portion extending from the offsetting portion and forming an upper support end. This form of hanger and the related top-wall structure allow the hanger member to be mounted with its offset portion at whichever one of several specific positions is closest to the center of gravity of the fixture, as determined by the particular choice of components within the housing.
Certain preferred embodiments also include a fastener which is used to secure the base portion of the hanger member to the inner surface of the top wall. Most preferably, the top wall of the housing has a pair of fastener apertures therethrough with the hanger-member apertures therebetween, and a fastener extends through one of the apertures (either a fastener aperture or a hanger-member aperture) into threaded engagement with the base portion of the hanger member, to hold the hanger member firmly in the desired location and in the desired orientation.
In this connection, it should be noted that, for any given hanger-member aperture, a hanger member may be mounted in a selected one of two possible orientations; with two orientations, two slots, and use of the proper aperture for purposes of securing the base portion of the hanger member to the top-member inner wall, there are at least four specific mounting positions possible. This allows the user to place the hanger member in the correct position to accommodate a particular weight arrangement, caused by the choices of power-related components, reflector, etc., which can greatly vary the center of gravity of the fixture.
It is particularly preferred that the hanger-member apertures be substantially parallel slots, and that the series of hanger-member portions be a series of flat portions. Most preferably, the hanger member comprises a flat plate with a series of substantially right-angle bends therein to form the flat portions. Such flat plate is dimensioned to be incapable of twisting in either of the slots.
The hanger member as described above is attached directly to the housing of the overhead industrial light fixture, and such hanger-member attachment using the preferred embodiment just described allows multiple specific positions for the hanger member. In some cases, however, such as when a junction box is to be attached to the fixture housing, the hanger member can be mounted to the junction box. In preferred embodiments of this sort, the junction box has a second pair of adjacent hanger-member apertures therethrough, such second pair of hanger-member apertures being positioned and arranged to provide at least three (or in some cases at least four) positions for mounting the hanger member. This further enhances the versatile mounting which is a part of certain preferred embodiments of this invention. Such hanger-member apertures in the junction box are also preferably slots.
When a junction box is used, it is preferred that the relationship of junction box with fixture housing allow the fixture to be suspended from the junction box in a partially-installed position while wiring work is done. To that end, the top wall of the housing has a center region, as indicated above, and one of the sidewalls joining the center region of the top wall at a common edge forms a spaced pair of hook-hold openings along the common edge, each hook-hold opening terminating upwardly in a pivot edge. A junction box is secured to the housing in position adjacent to the center region, and the junction box has a pair of hooks each projecting into one of the hook-hold openings and upwardly around the pivot edge thereof. This allows the fixture to safely hang on the junction box hooks during installation or service without being fully secured to the junction box.
In the most preferred of such embodiments, the junction box has first and second edges and the hooks project from the junction box along the first edge thereof, while a securing tab projects downwardly from the second edge (the opposite edge) of the junction box. The tab is preferably in the form of an inverted J-shaped fastener-engaging slot configured and arranged for engagement with the housing, preferably by means of a fastener.
In certain preferred embodiments having a junction box for swinging support of the fixture at hook-hold openings in one of the housing sidewalls, the sidewall has an inwardly-bent first tongue portion which forms each of the hook-hold openings, such first tongue portion extending toward the top wall at an acute angle with respect thereto. In such embodiments, it is preferred that the center region of the top wall have a downwardly-bent second tongue portion adjacent to each of the first tongue portions, the first and second tongue portions of each pair of tongue portions having distal edges which are closely adjacent to one another, such that the tongues are coplanar. In such embodiments, the first and second tongue portions together define a protected wire passageway within the fixture housing, along the common edge of the top wall and sidewall.
The present invention is also an improvement in overhead light fixtures of the type including (1) a housing having a top wall with inner and outer surfaces and a region defining a hanger-member aperture therethrough and (2) a hanger member formed of a series of portions including: (a) a base portion secured to the inner surface adjacent to the hanger-member aperture, (b) a through portion extending through the hanger-member aperture, (c) an offsetting portion extending from the through portion laterally along the outer surface, and (d) an offset portion extending from the offsetting portion and forming an upper support end. In the improved overhead light fixture, the top wall has a pair of securing devices thereon positioned with the hanger-member aperture therebetween such that the hanger member can be secured to the top wall in a selected one of two orientations. Thus, its offset portion may be at a selected one of two different positions, to accommodate different centers of gravity in the light fixture.
In preferred embodiments, as already noted, each of the securing devices is a fastener aperture in the top wall, and a fastener extends through one of the apertures into engagement with the base portion of the hanger member, preferably into threaded engagement.
This invention also is a combined light fixture and hanger set for overhead mounting thereof, the fixture being of the type described above and each of the hangers of the set being in the form described above. However, the hanger set includes at least two hanger members having offsetting portions of differing lengths. Thus, a selected one of the hanger members may be mounted with its offset portion in multiple mounting positions and the differing hanger members in the set further increase the number of mounting positions.
As used herein, the following terms have the meanings given below, unless the context requires otherwise:
In referring to an overhead industrial light fixture, the term xe2x80x9coverheadxe2x80x9d refers to fixtures which are typically mounted, directly or indirectly, on ceilings or overhead structural members of some sort, such as in factories, warehouses, etc. (regardless of purpose), or any other overhead structure put in place for the purpose of supporting a light fixture. The term xe2x80x9cindustrialxe2x80x9d is used in order to differentiate from residential lighting or the like. Neither of these terms is to be taken as limiting.
The term xe2x80x9cpower-related componentsxe2x80x9d includes ballasts, capacitors, ignitors and other devices for creating the proper electrical power usable for a selected lamp, such as high-intensity discharge (HID) lamps of various kinds.
The term xe2x80x9csubstantially enclosed,xe2x80x9d as used with respect to a space within a housing, means surrounded, but does not mean closed from the inflow and outflow of air. Indeed, as can be seen in the drawings, certain of the walls of the housing are heavily vented to allow essentially unrestricted inflow and outflow of air, for purposes of cooling. This invention involves enclosure of power-related components and recessing of the socket into the housing, and for these reasons cooling by convection flow is of great importance.
As used with respect to the socket, the term xe2x80x9csubstantially withinxe2x80x9d does not rule out protrusion of a small portion of the lamp-receiving end of the socket from the housing, through the socket window.
The term xe2x80x9clow-profilexe2x80x9d as applied to a lighting fixture means that the fixture is lower in profile than occurs when the socket is not recessed into the housing.
The terms xe2x80x9ctopxe2x80x9d and xe2x80x9cbottomxe2x80x9d used herein with reference to the fixture, or parts thereof, assume the normal use orientation of the fixture.
The overhead industrial light fixture of this invention, in its various forms, overcomes certain problems and shortcomings of the prior art, including those referred to above.